intl_translation_xliff
Extract intl messages to XLIFF and generate translations from XLIFF files
XXliff v1.2 - SpecificationXXliff v2.0 - Specification
See full guide a intl_translation_format.
If you only need XLIFF, you can execute the same commands from intl_translation_format with this package.
pub run intl_translation_xliff:extract --format xlf2
Available Formats
xlfxlf2